Abstract: A method of improving the post-combustion heat recovery in a basic oxygen furnace by controllably forming a foamy slag. The foamy slag is generated by increasing the lance height and reducing the rate of lance height reduction during the oxygen blowing cycle. The foamy slag is controlled to prevent slopping by calculating the approximate starting point of the peak decarburization period for the charge and then adjusting the oxygen flow rate to be at a minimum at the commencement of the peak decarburization period.

Abstract: An electric arc furnace includes at least one electrode projecting into a furnace vessel for containing a charge to be heated and electrode support structure for moving the electrode in a direction along a path towards and away from the charge. An improvement to the electric arc furnace comprises a sensor for detecting the position of the electrode support structure from an initial position. A processor calculates one of a support structure travel distance from the initial position and a rate of electrode consumption. An alarm signal is generated in response to at least one of the travel distance and the rate of electrode consumption being at least equal to a respective predetermined threshold travel distance or a predetermined threshold rate of electrode consumption, either of which is indicative of an excess electrode consumption condition for a given heat.

Abstract: A method of making ultra-low carbon, ultra-low sulfur content steel comprising introducing molten metal and slag into a vacuum decarburizer to reduce the carbon content of the metal to below 0.005%, followed by deoxidizing the molten steel, deoxidizing the slag and mixing the slag with the molten steel to reduce the sulfur content to below 0.005%.

Abstract: A method of making stabilized ultra-low carbon steel having a high nitrogen content for enameling applications. The preferred method involves two phases. The first phase occurs in the basic oxygen furnace wherein nitrogen gas is combined with oxygen gas and blown into the melt through the oxygen lance. After the oxygen blow the carbon content of the melt is approximately 0.03% and the nitrogen content is at least about 0.016 to 0.020%. In the second phase the melt is introduced to a vacuum circulation decarburizer where the carbon content of the steel is reduced to ultra low levels on the order of 0.005%. The nitrogen content is maintained at a level of at least about 0.01% by introducing nitrogen gas into the vacuum decarburization vessel as the lift gas through inert gas tuyeres.

Abstract: The present invention provides a new and improved method and apparatus for tapping molten metal through the tap hole of a metallurgical vessel. The apparatus utilizes a ladle or a BOF furnace or other metallurgical vessel used for the containment of molten metal. At least one extension drive mechanism is attached to the support structure to position the distal end of a lance within the vessel a predetermined distance above the surface of its contents. The lance is connected to an inert gas source such as Argon. Once the lance is properly positioned, the inert gas is directed onto the surface of the molten metal to prevent the slag from entering the tap hole. An alignment drive can also be attached to the support structure to adjust the position of the extension drive relative to the vessel so that the lance may be properly positioned within the vessel above the tap hole.

Abstract: Apparatus for continuously casting strip material comprising a casting drum rotatable about a first axis, a pair of cheek members including portions slidably engageable with sides of the casting drum mounted for rotation about a second axis spaced from said first axis and a casting belt wrapped around a portion of the cheek members together defining a converging casting arc. The cheek members include peripheral surfaces engageable by marginal edges of the casting belt which maintain a variable casting gap between a casting surface on the belt and a casting surface on the drum. The eccentric mounting of the cheek members with respect to the casting drum cause the spacing between the belt and the drum to decrease as the end of the casting arc is reached. The cheek members each include tapered side surfaces which together with the casting drum define ear receiving recesses that increase in a radial direction as the end of the casting arc is approached.

Abstract: The apparatus includes a generally cylindrical windscreen member attached to the bottom of a ladle with its axis generally vertical and concentric with a tap hole in the bottom of the ladle through which molten metal flows when released by a valve. An apertured cover plate is telescopically fitted over the windscreen. The cover plate is supported by a wire harness assembly coupled to the underside of the ladle for suspending the cover plate in a hanging relationship beneath the ladle. Lift line apparatus is provided for changing the elevation of the cover plate with respect to the ladle and windscreen in response to changes in the application of tension to the lift line. The cover plate is configured to rest upon, and form a seal with, the upper rim of an ingot mold when the cover plate is lowered while positioned above and aligned with the ingot mold. The windscreen and cover plate are made from a fibrous ceramic low density material to facilitate manual handling.

Abstract: The toughness of vanadium and niobium microalloyed medium carbon bar steels is significantly improved by a controlled addition of aluminum in a range of from about 0.05 to 0.11 percent. Forged parts combining high strength and hardness properties with improved toughness can be made from the new bar steel without the need of heat treatment.

Abstract: Corrugations are removed from the end of a helically corrugated pipe by compressing the end of the pipe between a plurality of radially movable die segments. By choosing appropriately-shaped die segments and die-actuating cams, the end of the pipe can be expanded, or shrunk to a diameter less than that of an imaginary cylinder defined by a surface of revolution contacting the innermost surfaces of the pipe. Products manufactured in accordance with the method of the invention have an end portion with an accurately controlled diameter; a minimum of pipe length is taken up by the modification.

Abstract: An eddy current inspector for imaging of a workpiece shape. A differentially wound test coil mounted next to a workpiece path of travel is energized with a time varying signal to set up eddy currents in the workpiece. A field modifying sleeve is rotated with the field to periodically disrupt the eddy current inducing field. Two signals from the coil, a flaw signal and a shape signal, are time multiplexed and scaled to present a real time image of a workpiece surface as well as the orientation and severity of flaws existing at the workpiece surface.

Abstract: An apparatus and method for providing a protective gas shroud around molten metal being teemed from a ladle having a slide gate secured to the bottom. The apparatus comprises a plenum box sealed to and extending downwardly from the sliding part of the slide gate. A hood is arranged to telescope over the plenum box and form a rough sliding seal therewith. The hood has a skirt flange at the bottom thereof. The width of said skirt flange in the direction of movement of the slide gate is greater than the maximum slide gate movement. Means are fixed relative to the plenum box to raise and lower the hood. Means are provided for introducing a protective gas into the plenum box. The method comprises aligning the ladle with the mold into which hot metal is to be teemed. The means for raising and lowering the hood is activated to lower the skirt flange to rest upon the top of the mold or hot top. Thereafter the slide gate is opened dragging the hood over the top of the mold or hot top into alignment with the mold.